1. Field of the Invention
The present invention relates to a gas generating device that includes a housing filled with a gas generating agent generating a gas during combustion and a squib accommodated in the housing to ignite the gas generating agent.
2. Description of Related Art
Both now and in the past, among gas generating devices, there is known a gas generating device disclosed in JP-A-2001-88653, which has a combination in which a housing includes a holder holding a squib, a cup-shaped metallic bottomed housing body accommodating a gas generating agent, and a connector connecting the holder and the housing body to each other. In the gas generating device disclosed in JP-A-2001-88653, an annular contact portion is formed at the peripheral edge of an opening of the housing body so as to protrude in a flange shape. Then, in the gas generating device disclosed in JP-A-2001-88653, the housing body is connected to the holder by using a connector that is formed around the annular contact portion and presses the annular contact portion toward the holder in the axial direction of the housing body. More specifically, in the gas generating device, a caulking portion formed as the connector in the holder is pressed and caulked in the axial direction of the housing body so as to cover the entire periphery of the rear surface side of the outer peripheral surface of the annular contact portion, whereby the housing body and the holder are connected to each other.
However, in the gas generating device disclosed in JP-A-2001-88653, the holder is also formed of metal. For this reason, a so-called metal contact occurs in a wide surface between the annular contact portion and the portion of the holder coming into contact with the annular contact portion during a caulking operation of the caulking portion, so that air-tightness is difficult to be ensured.
Then, in order to solve the problem, there is known a gas generating device having a configuration disclosed in JP-A-2002-200966. In the gas generating device disclosed in JP-A-2002-200966, an O-ring is accommodated in a portion of a holder coming into contact with an annular contact portion so as to ensure air-tightness around the connection portion between a housing body and the holder. However, in the gas generating device disclosed in JP-A-2002-200966, a groove needs to be formed by cutting in the holder so as to accommodate the O-ring therein, and the O-ring is also needed. For this reason, it is necessary to make the configuration simpler, and to reduce the number of manufacturing steps and manufacturing cost.
Further, there is known another gas generating device in JP-A-2003-161599. In the gas generating device, a holder holding a squib includes a metallic holder body and a resinous molding portion interposed between the holder body and the squib and formed of a synthetic resin.
Of course, JP-A-2003-161599 discloses a configuration in which the holder holding the squib includes the resinous molding portion which covers the outer peripheral side of the squib on the side of an ignition portion and the holder body which is disposed at the outer peripheral side of the resinous molding portion and is disposed on the side of a conductive pin distant from the ignition portion in the squib. However, a housing body connected to the holder is not mentioned in JP-A-2003-161599. Further, a method of connecting the housing body is not mentioned. In the holder disclosed in JP-A-2003-161599, a groove is formed throughout the entire periphery of the peripheral surface of the resinous molding portion (refer to FIG. 1). It is supposed that the groove is used to insert an O-ring therein to improve air-tightness in the housing body. For this reason, even in the gas generating device disclosed in JP-A-2003-161599, it is supposed that the air-tightness in the housing is ensured by using the O-ring.